1. Technical Field of the Invention
The present invention relates to a multi-chamber heat treatment device and its temperature control method which heat-treats an object to be treated in a heating chamber, and then moves the object into a cooling chamber to perform cooling treatment in the cooling chamber.
2. Description of the Related Art
A multi-chamber heat treatment device is a heat treatment device which includes a heating chamber which heat-treats an object to be treated, and a cooling chamber which performs cooling treatment on the object heat-treated in the heating chamber, and conveys and performs heat treatment of the object between the heating chamber and the cooling chamber.
In this multi-chamber heat treatment device, when the temperature of the object during heat treatment needs to be measured, conventionally, as disclosed in Patent Document 1, a temperature sensor is attached to the object, and the object is conveyed along with a data recorder which stores the temperature detection result from the temperature sensor.
That is, in this case, the data recorder exists along with the object in the heating chamber and the cooling chamber. Since this data recorder is heat-treated together with the object, the data recorder is housed in a case which has excellent heat resistance and heat insulation performance. Also, the data recorder is taken out from the inside of the cooling chamber after the completion of the cooling treatment on the object, and the temperature of the object during heat treatment is taken from the temperature detection result stored in the data recorder.
However, the means of Patent Document 1 had a problem in that the arrangement space for the object in the heating chamber and the cooling chamber becomes narrow, and the temperature of the object cannot be measured in real time.
Thus, in order to solve this problem, the inventor of the invention has invented and already filed the inventions of Patent Documents 2 and 3.
Patent Document 2 aims at reducing the space exclusively possessed by the temperature measuring unit arranged in a heat treatment furnace, securing the wide arrangement space for the object in the heat treatment furnace, and measuring the temperature of the object arranged in the heat treatment furnace in real time.
Therefore, as shown in FIG. 1, this invention is a multi-chamber heat treatment device including at least a heating chamber 53 which heat-treats an object to be treated X, and a cooling chamber 52 which performs cooling treatment on the object X which is heat-treated in the heating chamber 53. The device includes a sensor part 51 which is fixed to a predetermined spot of a tray for conveying the object X, a measuring part (not shown) which is electrically connected to the sensor part 51 and is arranged outside, a connection line 54 which has the sensor part 51 connected to one end thereof and has the measuring part connected to the other end thereof and thereby eclectically connecting the sensor part 51 and the measuring part, and a reel part (not shown) which is arranged in the cooling chamber 52 and is capable of winding the above connection line 54.
Patent Document 3 aims at securing the wide arrangement space for the object in the heating chamber and the cooling chamber, and measuring the temperature of the object in real time to perform cooling control accurately.
Therefore, as shown in FIG. 2, this invention is a multi-chamber heat treatment device including at least a heating chamber 53 which heat-treats an object to be treated X, and a cooling chamber 52 which performs cooling treatment on the object X which is heat-treated in the heating chamber. The device includes a temperature sensor 51 which detects the temperature of the object in the cooling chamber 52 and outputs a temperature detection signal indicating the temperature, a cooling control part 56 which is arranged outside the heating chamber and the cooling chamber and controls cooling treatment on the basis of the temperature of the object in the cooling chamber which is indicated by the temperature detection signal input from the temperature sensor 51, and a connection line 54 which connects the temperature sensor and the cooling control part.
Patent Document 1: Japanese Patent Application Laid-Open No. 9-280968
Patent Document 2: Japanese Patent Application Laid-Open No. 2005-241132
Patent Document 3: Japanese Patent Application Laid-Open No. 2007-46123
However, in the above-described Patent Documents 2 and 3, since there is no fixing means for receiving the tension which acts on the connection line 54, there is a possibility that the object loaded into the heating chamber is likely to move when winding tension is high. Therefore, the inventions cannot be applied to a large-sized furnace through which the reel part needs to be wound for a long distance.
Additionally, in the case of the multi-chamber heat treatment device of Patent Documents 2 and 3 described above, there is a problem in that the vacuum shielding door of the cooling chamber cannot be sealed while the object is heat-treated in the heating chamber.
Therefore, the gas atmosphere in the cooling chamber may become the same as that of the heating chamber during heating treatment of the object. As a result, there is a problem in that, after the object is housed in the cooling chamber after heating treatment, the cooling chamber needs to be decompressed again, and the gas atmosphere needs to be readjusted.
Additionally, since the heat insulation door is closed in a state where the signal line is bitten by the heat insulation door of the heating chamber while the object is heat-treated in the heating chamber, there is a problem that the gap between the heat insulation door and the signal line is large, and the heat leaks to the outside during heating.